One proposed hybrid vehicle has a driving system where a planetary gear unit functions to mutually connect a crankshaft of an engine, a drive shaft, a rotating shaft of a generator (see, for example, Japanese Patent Laid-Open Gazette No. 10-295003). In response to a demand for a non-driving state, a vehicle control device mounted on the hybrid vehicle regulates a rotation speed of the generator within an allowable rotation speed range, thus preventing the over speed of the generator.